Many of the workers arrived in November, just as the downturn began to hit.

Several protesters said they had paid large sums of money to Romanian and Chinese intermediaries companies in return for what they believed were long-term contracts on construction sites.

In reality companies failed to obtain work permits and an official said many of the workers were employed illegally.

The Chinese embassy has said it is trying to assist the workers, but an official at the Romania-China Chamber of Commerce said that hundreds, if not thousands of Chinese workers had been stranded.